Retouching table



p w. w. DAVIDSON. JR.. ET AL RETOUCHING TABLE Filed Nov. 18, 1938 2 Sheets-Sheet l flu/amps;

Patented Sept. 24, 1940 UNITED STATES PATENT OFFICE RETOUCHING TABLE I poration' of Illinois Application November 18, 1938, Serial N 0. 241,106

13 Claims.

The present invention relates to retouching tables for use in retouching photograph negatives and other reproductions, pictures and tracings requiring that the source of illumination be located on the opposite side thereof away from the operator.

Although retouching tables have been in use for some time, their construction and operation have met with certain objections and difllculties.

1:) Eye fatigue has been pronounced due to the glare of the illuminated border around the work piece on the table. Body fatigue and inconveniences arising from working at the tables long hours in uncomfortable positions, and difilculty 1:3 in adjusting the top of the table as to tilt without changing the height have been important factors also.

Work comfort for an artist, draftsman, architect, or any other person working at a table, de-

29 mands that the height and location of the front edge, the edge over whichthe operator leans while working, be located at the proper height' with regard to the operator's body at all times, so that the worker may bend over the table com- 25 iortably to reach the work if he has to be directly above it, or, if he cannot lean over the table comfortably, it is very desirable to have the table top tiltable without affecting the height of the front edge so that the work is brought nearer to the 30 level of the eye along an are equivalent to that which would be followed by the eye if the operator had leaned over the table. Consequently, it is one of the objects of the invention to provide a retouching table having these advantages and 35 characteristics.

Another object of the invention is to provide a retouching table wherein the work is illuminated uniformly from underneath without shadows-and without any glare existing around the work.

Another object of the invention is to provide a tiltable top for a retouching table which may be tilted to any desired plane, and the translucent portion thereof can be rotated in that plane so that the position of a photograph negative mounted upon the translucent portion may be worked upon from any angle without making it necessary for the operator to change his position from one directly in front of the table.

Another object is to provide a mounting for the rotatable portion of a table of the class mentioned which is within the confines of the top proper, and functions without the use of lubricant, whereby the danger of oil stains is elimiu nated.

Another object of the invention is to provide an improved retouching table of a character simple and inexpensive to construct, easy to adjust and operate, and thoroughly satisfactory in use. 5

These being among the objects of the invention, other and further objects will become apparent from the drawings herein, the description relating thereto and the appended claims.

In the drawings,

Fig. 1 is a perspective view of the preferred embodiment of the invention showing the table portion raised to a tilted position;

Fig. 2 is an enlarged vertical section of the embodiment illustrated in Fig. 1 showing the reflector and the manner in which the translucent portion is mounted for rotation in the tiltable top of the table.

Fig. 3 is an enlarged section showing the construction of the preferred means for mounting go the rotatable portion in the top of the table;

Fig. 4 is a perspective, partially cut away view of the mounting means illustrated in Fig. 3;

Fig. 5 is a view similar to Fig. 4 showing a modification of the means for mounting the rotatable portion in the table top; and

Fig. 6 is a reduced section similar to Fig. 2 showing a modification of the reflector and light control.

Referring now to the drawings in detail, the stand portion of the retouching table is made of four vertically disposed angle members arranged in two pairs of front and rear members 10 and I2, respectively. The angle members are preferably made of light metal and the members It) and i2 of each pair are secured together horizontally by two vertically spaced fiat members H which are welded at their ends to the angle members, to provide the two sides of the stand. The two sides are then secured together with four transverse rods I6 by hex-headed bolts I8 exprovided which is simple in construction and easy to dismantle.

A rectangular bed 20 made preferably of cast iron is supported on the stand at the top of the angle members l0 and I! by front and rear are to be described later.

straps 22 and 24, respectively. The straps are pivotally mounted at the sides of the bed close to the front and rear corners thereof where the bed is provided with downwardly extending lugs 26 to which the straps are secured by bolts 28.

The front straps 22 are of a width approximately that of the included faces of the angle members lfl-and are provided with longitudinal slots 29 therein at their lower ends which receive in sliding relationship suitable recesses 38 upon the nuts 3i. The engagement between the recesses 38 and the slots 29 prevents relative rotation, and threaded bolt members 32 are supported on opposite sides of the angle members [0 a shortdistance from the tops thereof to draw the nuts 3! against the straps 22 to clamp and hold them at any adjusted height so that the front edge of the table 20 may be located at a height desired independently of an movement of the rear straps 24. Radlally ex ending handles 34 are employed to drive the threaded members 32.

The rear straps 24 are employed to regulate the tilt of the bed 28, and for this purpose are releasably clamped intermediate their ends between clamp members 36 which are secured to the angle members I2 at the top thereof by bolts 38, the clamping relationship being established by means of knurled head bolts 40 which are threaded to draw the clamp members 36 together against opposite faces of the rear straps 24.

The bed 20 is provided with a rotatable translucent portion 42, and in mounting the translucent portion, a large circular opening 43 is molded and machined in the center of the bed. The opening 43 is provided with two vertically spaced cylindrical surfaces of different diameters wherein the larger of the two cylindrical surfaces 44 is next to the upper side of the bed so as to provide an upwardly facing shoulder 48 between it and the smaller of the cylindrical surfaces 45.

The translucent portion 42 comprises a ring member 5'!) recessed on its upper face as at 52 to receive flush therewith a translucent medium 54 made of milk glass or a clear glass etched upon its lower surface. The glass 54 is supported marginally all the way around upon the ring member 50 so that the space below the glass is free and clear of obstructions which would cause shadows to be cast thereon with a light below it.

In mounting the translucent portion 42 in the circular opening 43 of the bed, the outer edge of the ring 50 is bounded by two vertically spaced cylindrical surfaces of different diameters with the one 58 having the larger diameter located at the top so as to provide a downwardly facing shoulder 60 between it and the smaller cylindrical surface 56. The relative sizes of the cylindrical surfaces on both the bed 28 and the ring 50 are such that the two shoulders 48 and 60 overlap each other.

The two shoulders are channeled to provide raceways for the ball bearing 10 and when the balls of the ball bearing are in place, the shoulders are spaced 2. sufficient distance axially from each other to bring the top of the translucent portion 42 coplanar with the top of the bed 20. The two larger cylindrical surfaces 44 and 56 are also channeled as at 62 and 64, respectively, to provide raceways for a ball bearing 64.

Bearing spacers 68 and i2 are located between the larger cylindrical surfaces 44 and 56, and the shoulders 48 and 60, respectively. The spacer 12 rides in frictional engagement upon the shoulder 48 and carries the weight of the spacers 68 which A drag is thus effected for the movement of the balls which prevents a spinning of the translucent portion once it is set in rotating motion. Thus, the rotatable portion turns no faster than it is moved and stops quickly in its imposed position whenever the operator ceases to turn it.

The spacers 68 comprise arcuate sections 69 all of which. have tooth extensions ii on both ends, except one, 69a, which has a tooth only upon one end. The teeth are designed to subtend the balls 68 and thereby be held in place against removal as long as the balls in turn are held in evenly spaced relation by the spacers, a mutual supporting relationship being thus established when the bearing 64 is assembled.

When assembling the bed 28 and the translucent portion 42, the ball bearing 10 and the spacer 1'2 are first positioned in the raceway upon the shoulder 48. The ring 58 is then lowered carefully into place. The ring 50 is then pushed radially until the cylindrical surfaces 44 and 58 meet at one side and the balls 66 used in the bearing are then inserted between the surfaces 44 and 58 upon the opposite side. Thereafter the ring 50 is returned to its position where the cylindrical surfaces are concentric, and the arcuate sections 69 are inserted into place one at a time with a ball between each two of them until only space for one more spacer remains. Then the spacer 68a is slipped into place with the toothed end thereof introduced first and the untoothed end dropped into place. The spaced relation of all of the balls in the bearing is thereby established and assemblage completed. The table top and the ring are thus supported against relative radial displacement under all working conditions, regardless of what position the table top is tilted to.

Referring at this time to Fig. 5, a modification of the means by which the rotatable portion is mounted in the bed is illustrated, wherein the ring member 54aand the bed 20c: are provided with inclinc'i shoulders 48a and 68a, and a single bearing construction is employed. The shoulders are provided with raceways 18 that define conical surfaces of revolutions so that the ring member 50a is supported by a single ball bearing 19 against end thrust and radial thrust. In this embodiment, however, the assembled relationship between the bed 28a and the ring member 50a is maintained by a collar or retainer 88 suitably recessed into the tops of both the table and the ring to a position coplanar with the top of the table. The retainer 80 is preferably secured to the bed and the securement is accomplished by flush, fiat headed machine screws 82 threaded into the bed 20a. The retainer 80 not only holds the ring 50a in place but also prevents any erasure dust or other foreign particles from dropping into the bearings and causing wear and binding. A spacer 84 is provided for the bearing 19 and rides frictionally upon the shoulder 48a to provide a retarding effect upon the action of the ball bearing 29.

Although the friction between the spacer 12 or the spacer 84 and the respective shoulders 48 and 48a is generally enough to prevent a spinning of the rotatable member and will have a desirable braking action, yet a readily releasable clamping means 86 is provided to hold the translucent portion 42 positively in any relative position of its rotation. The means 86 as illustrated in Fig. 2 comprises a bracket 88 welded to the back side of the table with the upper end thereof bent to extend over the ring 50.

A knurled head bolt 90 is threadedly carried by the bracket on the bent over end and may be rotated to engage the ring 50 in clamping relationship.

Before passing on to a description of the means for illuminating the translucent portion, it may be well to point out at this time that certain further embodiments of the invention include protractor calibrations 92 along the edge of the ring member 50 in Fig. 1 with pointers or indexing lines 94 located upon the bed for reading the protractor scale. In the embodiment illustrated in Fig. 5, the protractor calibrations are placed upon the retainer 80 and it will be appreciated that the retainer shown may be one of several interchangeable retainers which have different calibrations for different purposes.

Moreover, a tray 96 for loose articles is provided upon the right hand side of the work table as illustrated in Fig. 1, and a rail 90 is secured along the front edge of the table top to keep pencils and other tools employed in retouching operations from rolling off of the top of the table when it is tilted. In addition to this, it will be appreciated that the rectangular shape of the table is such that a T-square can be used along any edge thereof.

Referring now to the means for illuminating the translucent portion from underneath, a deep concave reflector I00 made of sheet metal is secured to the bed independently of the rotatable portion 42 by screws I02. The shape of the reflector may be either parabolic or one in which the upper marginal edges thereof are substantially coextensive with the rectangular contour of the bed 20. The inside face of the reflector is covered with aluminum paint, or if it is parabolic in shape, it may be polished for purposes of high reflectivity and light control.

At the bottom of the reflector, a circular opening I04 is provided and a bracket I06 having a cylindrical flange I00 is secured thereto to support in a telescoping manner a cylindrical member I I0 which carries at the top thereof the lamp bulb H2. The cylindrical flange I08 is longitudinally slotted as at Ill to receive the nut and bolt assemblies II8 carried by the cylindrical member I I0 so that a relative telescoping adjustment may be had for thebulb II2 relative to the reflecting surface of the reflector I00. The nut and bolt assemblies II6 not only serve to regulate the height and the location of the lamp bulb I I2, but they may be loosened and the cylindrical member withdrawn to replace the lamp bulb when it burns out. Replacement of the lamp may thus be had without any need for removing the reflector or disturbing the bearing assembly between the ring and the table top.

Electricity for the bulb is furnished through the cord IIB which has in its circuit a control switch I20 secured to the angle member I0 where it is convenient for the operator.

With the adjustability afforded by the nut and bolt assembly II6, it is possible to more or less control the effective area of the illuminating light for photograph negatives of different sizes so that the border of the translucent member around any particular photograph negative may be made relatively dim to prevent eye strain and glare.

In certain installations where a wide range of sizes of photographic negatives are being retouched constantly, the area illuminated may be varied readily and sharply by means of an adjustable refractive medium, as shown in Fig. 6, where a modification of the invention is shown comprising a double convex lens I22'- of an inexpensive molded form mounted in a tubular portion I24 at the apex of a conical support I26. The lens is mounted in a frame I28 which is supported on a shaft I30 and the shaft I30 in turn is mounted for vertical movement in a guide member I32 supported by and forming a part of the tube I24. The shaft I30 has a rack I34 upon the back thereof and a gear I36 driven by a handle I38 meshes with the rack to raise and lower the lens to vary the area of the translucent portion illuminated.

In the cases where the size of the photograph is quite small and the concentration of light for that size would be too great,-a suitable means may be employed in the lighting circuit for dimming the source of light at will. Such a means could be a rheostat (not shown) or, as illustrated, the bulb provided may be one of a multiple fllament type suitably controlled. In either case, however, the border of the translucent portion around the photograph negative may be kept very dim and the intensity of the light directly illuminating the photograph can be varied in direct relation with the size of a photograph being worked upon so that all photographs, regardless of size, may be illuminated uniformly and with equal intensities.

Consequently, although several embodiments of the invention have been shown and described herein, it will be apparent to those skilled in the art that various and further uses, modifications and changes may be made without departing from the spirit and substance of the invention, the scope of which is commensurate with the appended claims. r

We claim as our invention:

1. A retouching table comprising a standard, a bed tiltably supported on the standard for movement to and from a horizontal position and having a circular aperture therein, a circular frame rotatably supported in said aperture, a translucent medium marginally carried exclusively by the frame, and lighting means supported under the translucent medium and movable as a unit with the bed.

2. A retouching table comprising a standard, a bed tiltably supported on the standard for movement to and from a horizontal position and havinga circular aperture therein, a frame, a translucent member marginally carried exclusively by the frame, means rotatably supporting the frame in the circular aperture including a retarded bearing, and lighting means supported as a unitary assembly with the frame under the translucent member.

3. A retouching table comprising a standard, a bed having a circular opening therein bounded by a bearing raceway, means pivotally mounting the bed on the standard an adjustable height, a circular frame bounded by a bearing raceway deflning a conical surface of revolution, frictionless bearing means between the raceways for rotatably supporting the frame on and approximately flush with the bed, protractor means for supporting the frame against axial displacement in one direction, a translucent medium marginally carried by the frame, and lighting means located beneath the translucent medium.

4. A table comprising a standard, a bed having a circular opening therein bounded by a bearing raceway, means pivotally mounting the bed on the standard proximate the front edge thereof, a circular frame bounded by. a bearing raceway, frictionless bearing means mounted in the raceways for rotatably supporting .the frame flush with the bed, a spacerfor the bearing means slidingly engaging one of the raceways, and lamp means marginally engaging the frame for retainling the same in any adjusted position.

5. A retouching table comprising a standard, a bed having a circular opening therein bounded by a bearing raceway, means pivotally mounting the bed on the standard an adjustable height, a circular frame bounded by a bearing raceway defining a conical surface of revolution, frictionless bearing means between the raceways for rotatably supporting the frame on and flush with the bed, means for supporting the frame against axial displacement in one direction, a translucent medium marginally carried by the frame, and

lighting means located beneath the translucent medium.

6. A retouching table comprising a standard, a bed having a circular opening therein bounded by a bearing raceway, means pivotally mounting the bed on the standard for movement to and from a horizontal position, a circular frame bounded by a bearing raceway, frictionless bearing means mounted in the raceways for rotatably supporting the frame on the bed, a translucent medium marginally carried by the frame, and lighting means located beneath the translucent medium supported as a unit on the bed and tiltably with the frame.

7. A retouching table comprising a standard, a bed tiltably supported on the standard and having a circular aperture therein, a circular central portion coplanar with the bed, cooperative bear ing raceways in the aperture and on the central portion, frictionless bearing members including a spacer located between the raceways, said spacer having an exposed face coplanar with the bed, and lighting means for illuminating the central portion.

8. A retouching table comprising a standard, a bed tiltably supported on the standard and having a circular aperture therein, a circular central portion, cooperative bearing raceways in the aperture and on the central portion, frictionless bearing members including a spacer located between the raceways, and lighting means for illuminating the central portion.

9. A retouching table comprising a standard, a bed tiltably supported on the standard and having a circular aperture therein, a circular central portion coplanar with the bed, cooperative bearing raceways in the aperture and on the central portion and having their upper edges spaced radially from each other, frictionless bearing members including a spacer located between the raceways, said spacer having an exposed face coplanar with the bed and closing the space between the radially spaced upper edges, and lighting means for illuminating the central portion.

10. A retouching table comprising a standard, a bed pivotally supported on the standard and having an aperture therein, translucent means rotatably mounted in the aperture, lighting means supported on the bed under the translucent means, and means controlling the refraction of the rays of light for varying the area of the translucent means lighted.

11. A retouching table comprising a standard, a bed pivotally supported on the standard and having an aperture therein, translucent means mounted in the aperture, a source of light supported on the bed under the translucent means, refractive means interposed between the source of light and the translucent means, and means for varying the position of the refractive means.

12. A retouching table comprising a standard, a bed supported on the standard and having an aperture therein, translucent means mounted in the aperture, reflector means supported on the bed under the translucent means. a source of light located in said reflector means, and means for varying the direction of the rays of the source of light to vary the concentration of light upon the translucent means about a fixed line perpendicular to the translucent means.

13. A retouching table comprising a standard, a bed having an aperture bounded by a bearing raceway, vertically sliding members adjustably secured to the front or the standard and pivotally supporting the bed at the front thereof, verti-- cally adjustable means at the back of the standard for raising and lowering the rear of the bed, a frame rotatably supported on the bed in said aperture and defining an unobstructed opening, a translucent medium covering said opening flush with the bed, protractor means for determining the extent of relative rotation between the'frame and bed, clamping means for locating the frame relative to the bed at any point of relative rotation and lighting means located beneath the translucent medium.

WILLIAM WARD DAVIDSON, JR. EDWARD FRANK DELL. 

